A conventional portable electronic device, such as a mobile phone, a wearable device, a tablet, etc., may suffer from the peak power consumption and the peak thermal impact problems (e.g. due to high instantaneous power consumption), where the peak power consumption may hurt the battery life of the conventional portable electronic device and may cause the system thereof to be unstable, and the unacceptable peak thermal impact may be dangerous to the user of the conventional portable electronic device. For example, when the battery of the conventional portable electronic device is full (e.g. the remaining battery power is around 100%), the battery supply voltage may be around 4.3 Volts (V), while in most cases, the battery supply voltage may be kept greater than or equal to 3.8 V. Under these operation conditions, the battery has more tolerance to peak power. But, when the battery supply voltage starts to drop (e.g. the battery supply voltage may be less than 3.8 V), the tolerance to peak power is getting worse, and therefore, any peak power may cause the system failure.
According to the related art, some conventional methods are proposed in order to solve the above problems. For example, one of the conventional methods may comprise using embedded thermal sensor for thermal shut-down decision. Another of the conventional methods may comprise passively monitoring the peak current-resistance (IR) drop (e.g. the peak voltage drop across a current-sensing resistance) with a limited sampling rate. However, further problems may be introduced. For example, the conventional methods measure results brought by peak power, thus are reactive but not proactive and may have poor response time. In addition, monitoring the peak IR drop may be inaccurate, resulting in greater and greater hardware area overhead to improve accuracy. Additionally, the sampling rate is typically limited, and therefore, it is hard to monitor at a full speed. Thus, a novel architecture is required for enhancing the system power management with fewer side effects.